信封 :

envelope

Relative explainations:

Examples:

1. 這個信封封得很嚴實。

The envelope was firmly sealed.

2. 寄信前，他在信封上寫上地址。

He addressed the envelope before mailing the letter.

3. 信封內裝有幾份附件。

There are several enclosures in the envelope.

4. 他用蒸汽把信封上的郵票揭下來。

He steamed the stamp off the envelope.

5. 我用了一個郵資已付的信封。

I use a prepaid envelope.

6. 他把郵票貼在信封上。

He glued a stamp onto the envelope.

7. 信封（的封口）沒粘住.

The (flap of the) envelope was unstuck.

8. 這個信封開了.

This envelope has come unstuck.